Your website navigation, your graphical design, and your directory/article structure should be determined by what it is you are trying to market. If you are marketing dog whistles then your site's category headers, links, images, flash, etc. should all be centered around dog whistles. If you are marketing yourself then the same is true. If you are marketing real estate for your area it should be obvious to the user what point you are getting across.
Your site should function around your marketing focus. Your main topics should be easy to get to and topics that relate but are not the focus of the site should be harder to get to because they are buried slightly.
Use primary navigation (top or left side) for main category or article navigation. Use secondary (right side, bottom) for less important topics. You may even consider linking to less important pages from pages other than your home page so that the primary articles stand out both to search engines and users.
Use images and logos to get your primary message across. If you have cool images for your secondary articles then put them on the appropriate pages.
As an exercise it is a good idea to sit back and look at the message your site is presenting. If we market it correctly Google will like it better, our users will like it better, and we will convert more clients.
